1. Field of the Invention
This invention relates to dollies having multiple supports and, in particular, to dollies with supports that are hingedly joined.
2. Description of the Related Art
Typically, dollies carrying a container comprise a wheeled platform to which a container is fixedly secured. For example, U.S. Pat. No. 5,074,572, which is incorporated herein by reference, issued to Delmerico et al. discloses a dolly which supports a single refuse container.
While dollies of this nature work well for their intended purpose, they have shortcomings. Often a user of such a dolly, such as a maintenance technician, is compelled to use multiple containers in performing his or her duties. For example, the technician may need one container to transport refuse and another container to transport recyclable goods. In addition, for those involved solely in recycling, different containers may be needed to transport each type of recyclable good (e.g., paper, plastic, glass, etc.). A single dolly transporting one container thus fails to satisfy the needs of these technicians.
U.S. Pat. No. 3,031,207 proposed a system in which two dollies could be connect by means of a pair of linking members. However, a rigid structure such as that disclosed in U.S. Pat. No. 3,031,207 lacks the ability to flex between the containers when one container is pulled (or pushed) onto a flooring which is at a different altitude (e.g., a threshold) whereas the other container remains on the previous flooring. U.S. Pat. No. 4,313,612 proposed a dolly system which inherently possesses the ability to flex slightly between containers. However, the system proposed in the U.S. Pat. No. 4,313,612 lacks the ability to temporarily rotate one support to an angle which is vertical approximately vertical with respect to the other horizontal support for purposes of storage. Of greater concern in the design of the system proposed in the U.S. Pat. No. 4,313,612 is the potential for the system to be disengaged when one container is pulled onto a flooring which is at higher altitude than the altitude of the flooring on which trailing containers (attached to the container being pulled) rest. This concern is warranted because the coupling therein may become disengaged when the leading container is lifted.
Some technicians have opted to string together multiple containers each of which is supported by a separate dolly. In stringing together the containers, the technicians often tie a handle of one container and to a handle on another container. The shortcomings with this solution are immediately apparent. First, the overall stability of the arrangement is poor. When pulling on a lead container, a trailing container may be prone to tipping when rounding a corner. Second, issues of sanitation are inherently present. For instance, when emptying the contents of a trash can into one of the containers, fluids and refuse may become trapped in whatever instrument is used to tie the containers together.
Accordingly, there is a need for a dolly transport system which is: (a) capable of transporting multiple containers; (b) capable of flexing between the containers when pulling one container onto a flooring with a different altitude; (c) stable and more maneuverable when rounding corners; (d) which provides the ability to rotate one platform with respect to an adjacent platform for storage purposes; and/or (e) which reduces or eliminates sanitation concerns.
A solution to one or more of the aforementioned deficiencies in the art can be obtained by the dolly herein described.
One embodiment of the invention contemplates a dolly for transporting multiple containers having at least two supports each of which has a top surface and an underside, at least one wheel mounted to of each of said at least two supports and extending below the underside of each of said at least two supports, at least two support mechanisms for supporting containers to the top surfaces of said at least two supports, and a hinge. In this embodiment a first of the at least two supports is attached to a second of the at least two supports by the hinge. Moreover, the wheels mounted to extend below the undersides of the at least two supports are preferably casters. In this embodiment the hinge defines a pivot line along which at least one wheel is mounted; the axis of rotation of this wheel is preferably fixed with respect to the supports. A dolly according to the first embodiment can rotate 360xc2x0 within a circle the diameter of which is the distance between an end of the first of said at least two supports and an end of the second of said at least two supports.
This embodiment contemplates adding a locking mechanism that allows the first support to be maintained at an angle with respect to the second support. Moreover, the support mechanisms include a first cylindrical boss which extends perpendicularly upward from the top surface of the first supports and has screw threads extending outwardly from the cylindrical boss. This embodiment may further incorporate a step point on which a user can place a foot to hold the dolly in a first fixed position when affixing a container to the dolly, and on which the user can place the foot to hold the dolly in a second fixed position when removing a container from the dolly.
A second embodiment of a dolly has at least two supports each having a top surface configured to receive a container and an underside, a first and a second of the supports being connected so as to be pivotable relative to one another about a pivot axis, a plurality of wheels, some of the wheels being connected to a first of the at least two supports and extending below the underside of the first of the at least two supports, some of the wheels being connected to a second of the at least two supports and extending below the underside of the second of the at least two supports, and at least one of the wheels being approximately coaxial with the pivot axis. In this embodiment, the first and the second supports are connected by a hinge which defines the pivot axis. Moreover, the second support bends toward the first support by means of being hingedly connected to the first support. This embodiment also contemplates adding a locking mechanism that allows the first support to be maintained at an angle with respect to the second support. In addition, and also similar to the first embodiment, the wheels mounted to extend below the undersides of the at least two supports are preferably casters allowing the dolly to rotate 360xc2x0 within a circle the diameter of which is the distance between an end of the first support and an end of the second support.
The second embodiment may also include at least two support mechanisms for supporting at least two containers to the top surfaces of the at least two supports. The support mechanisms include a cylindrical boss which extends perpendicularly upward from the top surface of the supports and have screw threads extending outwardly from the cylindrical boss.
Finally, the second embodiment may include a step point on which a user can place a foot to hold the dolly in a first fixed position when affixing a container to the dolly, and on which the user can place a foot to hold the dolly in a second fixed position when removing a container from the dolly.
The invention also contemplates a method for storing multiple containers which includes removing a first container from a dolly which supports at least two containers, nesting the first container in a second container supported by the dolly, rotating a portion of the dolly which supported the first container toward a sidewall of second container, and storing the dolly. The method may also include locking the portion of the dolly which supported the first container in a position which defines an angle with respect to a second portion of the dolly which supports the second container. The angle is preferably between 75xc2x0 and 105xc2x0.
Another invention of the present application includes a locking mechanism for use on a dolly which carries multiple containers. A locking mechanism of this nature includes a first hinge portion having a plurality of first fingers, each having at least one top beam and at least one bottom beam defining a first plurality of spaces, and a plurality of first posts between each of the first fingers, a second hinge portion having a plurality of second fingers, each having at least one top beam and at least one bottom beam defining a second plurality of spaces, and a plurality of second posts between each of the second fingers, a block attached to one of said first posts, and a bar journalled through the plurality of first fingers and through the plurality of second fingers thereby joining the first hinge portion and the second hinge portion. In this locking mechanism, the first fingers are fixedly engaged with the second posts and the second fingers are engaged with the first posts when the block is positioned in one of the said plurality of spaces. In addition, the first post to which the block is attached is preferably at an end of the first hinge portion. Finally, in the the locked position, the block is frictionally engaged with one of said second fingers.